Henin said Thursday she has a partially torn ligament in her right elbow. She hurt the elbow in a fall during the first set of her fourth-round match against Kim Clijsters at Wimbledon. Henin lost the match in three sets.
She said the injury will cause her to miss the U.S. Open, which begins Aug. 30.
Henin stepped away from the game in May 2008 but returned in January and finished second to Serena Williams at the Australian Open. She is 32-8 this year with two tournament championships.
Despite appearing in just eight tournaments, Henin had climbed to 16th in the WTA rankings.
Henin won seven major tournament titles and spent 117 weeks as the top-ranked women's tennis player before her 2008 retirement.